“For those whom he foreknew he also predestined to be conformed to the image of his Son, in order that he might be the firstborn among many brothers.”

What is the nature of the conformity that Paul speaks of in Romans 8:29? Ben Witherington writes of Romans 8:29-30:

“Symmorphous, conformed, probably does not have in view the conforming of the bleiever to the image of Christ that takes place internally and during the process of sanctification, or at least that is not the sole subject here. If it is referred to at all, it is referred to as part of the process that leads to the final act of conforming believers to Christ–namely the resurrection. Paul goes on to say that Christ becomes the firstborn of many brothers and sisters through this process. In view of 1 Cor. 15.20-24 this surely refers to Christ’s resurrection, his so-called birth (rebirth) being at the resurrection–first fruits and firstborn being two ways of speaking about the same thing, both of which imply that there will be more to follow. Kasemann is probably right to see the Adam story, grounded in the comparison in Romans 5, behind all of this. Christ is the first of a new race, the race of resurrected ones, who for now are being conformed internally but not yet externally to Christ’s image.

V. 30 then sums this all up, reassuring the Romans that God is in control of all these matters. Those believers whom God foreknew he also destined in advance, those he destined he also called, those he called he also set right, and those he set right he also glorified. The verb tenses make it clear that Paul is looking at things from the eschatological end of the process, with even glorification already having transpired. Doxa, “glory,” here refers to the future glory of the resurrection, as before. Paul’s emphasis here is on God’s hand of involvement in every step of this process, and so he does not mention the human response, positive or negative. Nor does he mention sanctification. But he has already spoken of believers loving God in v.28, and that should be kept in view thought the reading of vv. 29-30. If these latter two verses stood in isolation apart from a clear connection with v. 28, that would be one thing, but they do not, and they must be interpreted in light of the broader context of Pauline thinking about grace and faith, foreknowing and human purpose, and the like. If vv. 29-30 stood alone then Paul would indeed sound like the most deterministic of early Jews, such as we sometimes find in some early Jewish literature at Qumran and elsewhere. But what the Romans needed to be assured of was God’s involvement, not their own, in the whole salvation process and plan. This text admirably stresses the hands-on nature of God and his providential plan. This truth, when it comes to looking at the Christian life as an exercise in persevering, will be even further highlighted in vv. 31-39.”

Conformity seems, then, to be a change in human nature as a result of Christ’s resurrection–namely the change of human nature that is involved in the universal resurrection of the dead, and the consequential glorification of mankind. The conformity need not be an ethical change involved in the process of an individual’s salvation.